She went into the swamp as Zinnia and came out The Swamp Creature. At one point I thought she was stuck in the mud, but then she circled out and ran back in romping around like it was the most fun she could possibly have.
When she finally did come out of the swamp, she did a little grazing, as Swamp Creatures do, then returned to the path.
By the time we got back home, Zinnia was herself again. Most of the mud had dried or been washed off in the other small less mucky bodies of water along the way. I did hose her down before letting her in the house.